The two Cleveland police officers involved in the fatal shooting of 12-year-old Tamir Rice will face a new administrative review after an Ohio state grand jury decided not to press charges against them, Mayor Frank Jackson said Tuesday.
A City Council member, meanwhile, said Tuesday night that he would seek negligent homicide charges under city law.
Jackson said at a news conference Tuesday that regardless of what the grand jury in Cuyahoga County believed about Tamir's death on Nov. 22, 2014, "it should not have happened."
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"It should not have happened," he repeated. "It simply should not have happened."
County Prosecutor Timothy McGinty said Monday that it was "reasonable" for rookie cop Timothy Loehmann, who fired the fatal shots, to believe that they he was in danger when Tamir reached for what turned out to be a pellet gun.
"He had reason to fear for his life," McGinty said.
Loehmann and his partner, Frank Garmback, remain on restricted duty — "basically in an office doing paperwork" — pending the new review, Jackson said.
"I do not have a comment on what the grand jury did," he said. "Now, it's in our world, and we are going to do what we believe is the right thing."
Police Chief Calvin Williams said the administrative committee, which includes civilians, will start from scratch, beginning with the initial calls to 911.
"We are going to take a lot at that from start to finish," Williams said Tuesday. "Once we look at all the evidence, the facts are going to be what they are, and we'll go from there."
Late Tuesday, City Council member Jeffrey Johnson announced that he would ask the council to seek local charges of negligent homicide on Wednesday.
Johnson said on Twitter that misdemeanor negligent homicide "unfortunately" was the most serious charge that could be sought under city law. Conviction would carry a term of only six months in jail, but Johnson said the process would allow for another full review of the shooting.
"The officers owed a duty to the innocent #TamirRice which means they should have refrained from acting in a harmful way that caused death," he said.
The mayor and the police chief said the city was ready for protests, saying they welcomed them as a part of the healing process.
"People are upset, and legitimately and rightfully so," Jackson said.
"You have an expression of legitimate concern about the system," he added. "That's what I'm hearing."
Tamir's mother, Samaria Rice, released a statement Monday accusing McGinty of "deliberately" sabotaging the case.
Her attorneys and McGinty have sparred in the weeks leading up to the grand jury's decision, with Samaria Rice claiming that McGinty was leaking information from the investigation to the public and had unfairly used investigators who sided only with the officers.
"As the video shows, Officer Loehmann shot my son in less than a second," Samaria Rice said. "All I wanted was someone to be held accountable. But this entire process was a charade. I pray and hope that the federal government will investigate this case."
In addition to reviewing the conduct of the two officers, the Cleveland Police Department's Critical Incident Review Committee will also determine whether the 911 call taker and dispatcher should face disciplinary charges.
The dispatcher, who was criticized for how she handled the initial call, resigned in July after missing work for several months, according to reports. Investigators said she failed to tell the officers that the caller who reported that Tamir waving a gun said that he might be a juvenile and that the firearm he was holding was "probably fake."
Williams could not say how long the review would take.
Jackson, meanwhile, acknowledged that people are frustrated with the perceived "lack of fairness" in how cases are handled, and he promised a just administrative review.
"There is a legitimate concern," he said, "and we don't want to be a part of that."
This article first appeared on NBCNews.com.